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I Stockley - One of the best experts on this subject based on the ideXlab platform.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Orthopaedic Proceedings, 2018Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:IntroductionVancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement.MethodsA total of 18 cement discs of constant size, containing either proprietary CopalG+V®; or ‘home-made’ CopalR+G® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester.Results...
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comparison of the elution properties of commercially available gentamicin and bone cement containing vancomycin with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: N Frew, T Cannon, Tim Nichol, Thomas J Smith, I StockleyAbstract:Aims Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available, but are significantly more expensive. We investigated whether the elution of antibiotic from ‘home-made’ cement containing vancomycin was comparable with more expensive commercially available vancomycin impregnated cement. Materials and Methods A total of 18 cement discs containing either proprietary CopalG+V; or ‘home-made’ CopalR+G with vancomycin added by hand, were made. Each disc contained the same amount of antibiotic (0.5 g gentamycin, 2 g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two-week period. The concentrations of gentamicin and vancomycin in the fluid were analysed using high performance liquid chromatography mass spectrometry. Results The highest peak concentrations of antibiotic were observed from the ‘home-made’ cements containing vancomycin, added as in the operating theatre. The overall elution of antibiotic was, fivefold (vancomycin) and twofold (gentamicin) greater from the ‘home-made’ mix compared with the commercially mixed cement. The use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Conclusion These findings suggest that the addition of 2 g vancomycin powder to gentamicin-impregnated bone cement by hand significantly increases the elution of both antibiotics compared with commercially prepared cements containing vancomycin. We found no significant advantages of using expensive commercially produced vancomycin-impregnated cement and recommend the addition of vancomycin powder by hand in the operating theatre. Cite this article: Bone Joint J 2017;99-B:73–7.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2016Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:Introduction Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement. Methods A total of 18 cement discs of constant size, containing either proprietary CopalG+V ® ; or ‘home-made’ CopalR+G ® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester. Results Highest peak antibiotic concentrations were observed from the ‘home-made’ vancomycin containing cement, added as in the operating theatre. Overall antibiotic elution was, five-fold (vancomycin) and two-fold (gentamicin), greater from the ‘home-made’ mix compared to commercially mixed cement. However the ‘home-made’ cements showed greater variation in elution kinetics compared to the commercial mix. Use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Impact strength testing showed no significant differences between the groups. Discussion Our findings suggest the addition of 2g vancomycin powder to gentamicin-impregnated bone cement in theatre, significantly increases elution of both antibiotics, with no significant loss of strength, compared to commercially prepared cement. Conclusion We have found no significant advantages of expensive off-the-shelf vancomycin-impregnated bone cement and recommend the addition of vancomycin powder by hand when making cement beads and spacers.
Robert E Smith - One of the best experts on this subject based on the ideXlab platform.
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UPLC-QTOF-MS and NMR analyses of graviola (Annona muricata) leaves
Revista Brasileira de Farmacognosia, 2016Co-Authors: Ingrid Vieira Machado De Moraes, Kristy M Richards, Kevin Tran, Paulo Riceli Vasconcelos Ribeiro, Flávio Luis Schmidt, Kirley Marques Canuto, Guilherme Julião Zocolo, Edy Sousa De Brito, Robert E SmithAbstract:Graviola leaves ( Annona muricata L., ( ceae ) are used by some people to try to treat or even cure cancer, even though over-consumption of the fruit, which contains the neurotoxins annonacin and squamocin has caused an atypical form of Parkinson’s disease. In previous analyses, the fruits were extracted with methanol under ambient conditions before analyses. In the present study, UPLC-QTOF-MS and NMR were used to analyze freeze-dried graviola leaves that were extracted using dry methanol and ethanol at 100° C and 10MPa (100atm) pressure in a Sealed Container. Methanol solubilized 33% of the metabolites in the lyophilized leaves. Ethanol solubilized 41% of metabolites in the lyophilized leaves. The concentrations of total phenolic compounds were 100.3 ±2.8 and 93.2 ± 2.0 mg gallic acid equivalents per g of sample, for the methanolic and ethanolic extracts, respectively. Moreover, the toxicophore (unsaturated 7-lactone) that is present in neurotoxic acetogenins was found in the lipophilic portion of this extract. The concentrations of the neurotoxins annonacin and squamocin were found by UPLC-QTOF-MS to be 305.6 ± 28.3 and 17.4 ± 0.89 (xg/g-dw, respectively, in the dried leaves. Pressurized methanol solubilized more annonacin and squamocin than ethanol. On the other hand, a hot, aqueous infusion solubilized only 0.213% of the annonacin and too little of the squamocin to be detected. So, graviola leaves contain significant amounts of the neurotoxins annonacin and squamocin, as well as some potentially healthy phenolic compounds. Finally, the potential neurotoxicity of whole leaves in dietary supplements could be much higher than that of a tea (hot aqueous infusion) that is made from them.
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UPLC–QTOF–MS and NMR analyses of graviola (Annona muricata) leaves
Elsevier, 2016Co-Authors: Ingrid Vieira Machado De Moraes, Kristy M Richards, Kevin Tran, Paulo Riceli Vasconcelos Ribeiro, Flávio Luis Schmidt, Kirley Marques Canuto, Guilherme Julião Zocolo, Edy Sousa De Brito, Rensheng Luo, Robert E SmithAbstract:Graviola leaves (Annona muricata L., Annonaceae) are used by some people to try to treat or even cure cancer, even though over-consumption of the fruit, which contains the neurotoxins annonacin and squamocin has caused an atypical form of Parkinson's disease. In previous analyses, the fruits were extracted with methanol under ambient conditions before analyses. In the present study, UPLC–QTOF–MS and NMR were used to analyze freeze-dried graviola leaves that were extracted using dry methanol and ethanol at 100 °C and 10 MPa (100 atm) pressure in a Sealed Container. Methanol solubilized 33% of the metabolites in the lyophilized leaves. Ethanol solubilized 41% of metabolites in the lyophilized leaves. The concentrations of total phenolic compounds were 100.3 ± 2.8 and 93.2 ± 2.0 mg gallic acid equivalents per g of sample, for the methanolic and ethanolic extracts, respectively. Moreover, the toxicophore (unsaturated γ-lactone) that is present in neurotoxic acetogenins was found in the lipophilic portion of this extract. The concentrations of the neurotoxins annonacin and squamocin were found by UPLC–QTOF–MS to be 305.6 ± 28.3 and 17.4 ± 0.89 μg/g-dw, respectively, in the dried leaves. Pressurized methanol solubilized more annonacin and squamocin than ethanol. On the other hand, a hot, aqueous infusion solubilized only 0.213% of the annonacin and too little of the squamocin to be detected. So, graviola leaves contain significant amounts of the neurotoxins annonacin and squamocin, as well as some potentially healthy phenolic compounds. Finally, the potential neurotoxicity of whole leaves in dietary supplements could be much higher than that of a tea (hot aqueous infusion) that is made from them. Keywords: Graviola, Annona muricata, UPLC–QTOF–MS, Parkinson's disease, NM
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determination of neurotoxic acetogenins in pawpaw asimina triloba fruit by lc hrms
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Robert A. Levine, Kristy M Richards, Kevin Tran, Andrew L Thomas, Robert E SmithAbstract:The concentrations of the neurotoxins, annonacin and squamocin, were determined in a lyophilized sample of the fruit pulp of the North American pawpaw (Asimina triloba) by LC coupled to high resolution mass spectrometry or LC-HRMS. The sample was extracted using dry methanol at 100 °C and 10 MPa pressure in a Sealed Container. The extraction of annonacin and squamocin was optimal at 100 °C with 7.72 and 0.162 mg/g, respectively, being found. Also, several isomers of annonacin and squamocin were separated and detected but not quantified.
N Frew - One of the best experts on this subject based on the ideXlab platform.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Orthopaedic Proceedings, 2018Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:IntroductionVancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement.MethodsA total of 18 cement discs of constant size, containing either proprietary CopalG+V®; or ‘home-made’ CopalR+G® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester.Results...
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comparison of the elution properties of commercially available gentamicin and bone cement containing vancomycin with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: N Frew, T Cannon, Tim Nichol, Thomas J Smith, I StockleyAbstract:Aims Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available, but are significantly more expensive. We investigated whether the elution of antibiotic from ‘home-made’ cement containing vancomycin was comparable with more expensive commercially available vancomycin impregnated cement. Materials and Methods A total of 18 cement discs containing either proprietary CopalG+V; or ‘home-made’ CopalR+G with vancomycin added by hand, were made. Each disc contained the same amount of antibiotic (0.5 g gentamycin, 2 g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two-week period. The concentrations of gentamicin and vancomycin in the fluid were analysed using high performance liquid chromatography mass spectrometry. Results The highest peak concentrations of antibiotic were observed from the ‘home-made’ cements containing vancomycin, added as in the operating theatre. The overall elution of antibiotic was, fivefold (vancomycin) and twofold (gentamicin) greater from the ‘home-made’ mix compared with the commercially mixed cement. The use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Conclusion These findings suggest that the addition of 2 g vancomycin powder to gentamicin-impregnated bone cement by hand significantly increases the elution of both antibiotics compared with commercially prepared cements containing vancomycin. We found no significant advantages of using expensive commercially produced vancomycin-impregnated cement and recommend the addition of vancomycin powder by hand in the operating theatre. Cite this article: Bone Joint J 2017;99-B:73–7.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2016Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:Introduction Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement. Methods A total of 18 cement discs of constant size, containing either proprietary CopalG+V ® ; or ‘home-made’ CopalR+G ® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester. Results Highest peak antibiotic concentrations were observed from the ‘home-made’ vancomycin containing cement, added as in the operating theatre. Overall antibiotic elution was, five-fold (vancomycin) and two-fold (gentamicin), greater from the ‘home-made’ mix compared to commercially mixed cement. However the ‘home-made’ cements showed greater variation in elution kinetics compared to the commercial mix. Use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Impact strength testing showed no significant differences between the groups. Discussion Our findings suggest the addition of 2g vancomycin powder to gentamicin-impregnated bone cement in theatre, significantly increases elution of both antibiotics, with no significant loss of strength, compared to commercially prepared cement. Conclusion We have found no significant advantages of expensive off-the-shelf vancomycin-impregnated bone cement and recommend the addition of vancomycin powder by hand when making cement beads and spacers.
Thomas J Smith - One of the best experts on this subject based on the ideXlab platform.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Orthopaedic Proceedings, 2018Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:IntroductionVancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement.MethodsA total of 18 cement discs of constant size, containing either proprietary CopalG+V®; or ‘home-made’ CopalR+G® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester.Results...
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comparison of the elution properties of commercially available gentamicin and bone cement containing vancomycin with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: N Frew, T Cannon, Tim Nichol, Thomas J Smith, I StockleyAbstract:Aims Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available, but are significantly more expensive. We investigated whether the elution of antibiotic from ‘home-made’ cement containing vancomycin was comparable with more expensive commercially available vancomycin impregnated cement. Materials and Methods A total of 18 cement discs containing either proprietary CopalG+V; or ‘home-made’ CopalR+G with vancomycin added by hand, were made. Each disc contained the same amount of antibiotic (0.5 g gentamycin, 2 g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two-week period. The concentrations of gentamicin and vancomycin in the fluid were analysed using high performance liquid chromatography mass spectrometry. Results The highest peak concentrations of antibiotic were observed from the ‘home-made’ cements containing vancomycin, added as in the operating theatre. The overall elution of antibiotic was, fivefold (vancomycin) and twofold (gentamicin) greater from the ‘home-made’ mix compared with the commercially mixed cement. The use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Conclusion These findings suggest that the addition of 2 g vancomycin powder to gentamicin-impregnated bone cement by hand significantly increases the elution of both antibiotics compared with commercially prepared cements containing vancomycin. We found no significant advantages of using expensive commercially produced vancomycin-impregnated cement and recommend the addition of vancomycin powder by hand in the operating theatre. Cite this article: Bone Joint J 2017;99-B:73–7.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2016Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:Introduction Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement. Methods A total of 18 cement discs of constant size, containing either proprietary CopalG+V ® ; or ‘home-made’ CopalR+G ® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester. Results Highest peak antibiotic concentrations were observed from the ‘home-made’ vancomycin containing cement, added as in the operating theatre. Overall antibiotic elution was, five-fold (vancomycin) and two-fold (gentamicin), greater from the ‘home-made’ mix compared to commercially mixed cement. However the ‘home-made’ cements showed greater variation in elution kinetics compared to the commercial mix. Use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Impact strength testing showed no significant differences between the groups. Discussion Our findings suggest the addition of 2g vancomycin powder to gentamicin-impregnated bone cement in theatre, significantly increases elution of both antibiotics, with no significant loss of strength, compared to commercially prepared cement. Conclusion We have found no significant advantages of expensive off-the-shelf vancomycin-impregnated bone cement and recommend the addition of vancomycin powder by hand when making cement beads and spacers.
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the cement spacer with multiple indentations increasing antibiotic elution using a cement spacer teabag
Journal of Bone and Joint Surgery-british Volume, 2015Co-Authors: S Salih, Tim Nichol, Thomas J Smith, Aimee R Paskins, A J HamerAbstract:We investigated whether the indentation of bone cement spacers used in revision of infected joint arthroplasty with a MacDonald dissector increased the elution of antibiotic in vitro. A total of 24 cement discs containing either 0.17 g (0.88% w/w), 0.25 g (1.41% w/w), or 0.33 g (1.75% w/w) gentamicin of constant size were made. Of these, 12 were indented with the dissector. Each disc was immersed in ammonium acetate buffer in a Sealed Container, and fluid from each Container was sampled at zero, one, three, six, 24, 48 and 72 hours and at one, and two weeks. The concentration of gentamicin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The fluid sampled at 72 hours from the indented discs containing 0.17 g gentamicin (0.88% w/w) contained a mean of 113 mcg/ml (90.12 to 143.5) compared with 44.5 mcg/ml (44.02 to 44.90) in the fluid sampled from the plain discs (p = 0.012). In discs containing 0.33 g gentamicin (1.75% w/w), the concentration eluted from the indented discs at 72 hours was a mean of 316 mcg/ml (223 to 421) compared with a mean of 118 mcg/ml (100 to 140) from the plain discs (p < 0.001). At two weeks, these significant differences persisted. At nine weeks the indented discs eluted a greater concentration for all gentamicin doses, but the difference was only significant for the discs containing 0.17 g (0.88% w/w, p = 0.006). However if the area under the curve is taken as a measure of the total antibiotic eluted, the indented discs eluted more gentamicin than the plain discs for the 0.17 g (0.88% w/w, p = 0.031), the 0.25 g (1.41% w/w, p < 0.001) and the 0.33 g (1.75% w/w, p < 0.001) discs. When preparing antibiotic spacers for use in staged revision arthroplasty surgery we recommend indenting the spacer with a MacDonald dissector to increase the elution of antibiotic.
Tim Nichol - One of the best experts on this subject based on the ideXlab platform.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Orthopaedic Proceedings, 2018Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:IntroductionVancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement.MethodsA total of 18 cement discs of constant size, containing either proprietary CopalG+V®; or ‘home-made’ CopalR+G® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester.Results...
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comparison of the elution properties of commercially available gentamicin and bone cement containing vancomycin with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: N Frew, T Cannon, Tim Nichol, Thomas J Smith, I StockleyAbstract:Aims Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available, but are significantly more expensive. We investigated whether the elution of antibiotic from ‘home-made’ cement containing vancomycin was comparable with more expensive commercially available vancomycin impregnated cement. Materials and Methods A total of 18 cement discs containing either proprietary CopalG+V; or ‘home-made’ CopalR+G with vancomycin added by hand, were made. Each disc contained the same amount of antibiotic (0.5 g gentamycin, 2 g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two-week period. The concentrations of gentamicin and vancomycin in the fluid were analysed using high performance liquid chromatography mass spectrometry. Results The highest peak concentrations of antibiotic were observed from the ‘home-made’ cements containing vancomycin, added as in the operating theatre. The overall elution of antibiotic was, fivefold (vancomycin) and twofold (gentamicin) greater from the ‘home-made’ mix compared with the commercially mixed cement. The use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Conclusion These findings suggest that the addition of 2 g vancomycin powder to gentamicin-impregnated bone cement by hand significantly increases the elution of both antibiotics compared with commercially prepared cements containing vancomycin. We found no significant advantages of using expensive commercially produced vancomycin-impregnated cement and recommend the addition of vancomycin powder by hand in the operating theatre. Cite this article: Bone Joint J 2017;99-B:73–7.
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comparison of the elution properties of commercially available gentamicin and vancomycin impregnated bone cement with home made preparations
Journal of Bone and Joint Surgery-british Volume, 2016Co-Authors: N Frew, Tim Nichol, Thomas J Smith, I StockleyAbstract:Introduction Vancomycin is commonly added to acrylic bone cement during revision arthroplasty surgery. Proprietary cement preparations containing vancomycin are available but significantly more expensive. We investigated whether the antibiotic elution and mechanical strength of ‘home-made’ vancomycin containing bone cement was comparable to commercial vancomycin-impregnated cement. Methods A total of 18 cement discs of constant size, containing either proprietary CopalG+V ® ; or ‘home-made’ CopalR+G ® with vancomycin added by hand, were made. Each disc contained the same antibiotic quantities (0.5g gentamycin, 2g vancomycin) and was immersed in ammonium acetate buffer in a Sealed Container. Fluid from each Container was sampled at eight time points over a two week period. The concentration of gentamicin and vancomycin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The impact strength of each PMMA cement preparation was measured using a Charpy-type impact tester. Results Highest peak antibiotic concentrations were observed from the ‘home-made’ vancomycin containing cement, added as in the operating theatre. Overall antibiotic elution was, five-fold (vancomycin) and two-fold (gentamicin), greater from the ‘home-made’ mix compared to commercially mixed cement. However the ‘home-made’ cements showed greater variation in elution kinetics compared to the commercial mix. Use of a vacuum during mixing had no significant effect on antibiotic elution in any of the samples. Impact strength testing showed no significant differences between the groups. Discussion Our findings suggest the addition of 2g vancomycin powder to gentamicin-impregnated bone cement in theatre, significantly increases elution of both antibiotics, with no significant loss of strength, compared to commercially prepared cement. Conclusion We have found no significant advantages of expensive off-the-shelf vancomycin-impregnated bone cement and recommend the addition of vancomycin powder by hand when making cement beads and spacers.
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the cement spacer with multiple indentations increasing antibiotic elution using a cement spacer teabag
Journal of Bone and Joint Surgery-british Volume, 2015Co-Authors: S Salih, Tim Nichol, Thomas J Smith, Aimee R Paskins, A J HamerAbstract:We investigated whether the indentation of bone cement spacers used in revision of infected joint arthroplasty with a MacDonald dissector increased the elution of antibiotic in vitro. A total of 24 cement discs containing either 0.17 g (0.88% w/w), 0.25 g (1.41% w/w), or 0.33 g (1.75% w/w) gentamicin of constant size were made. Of these, 12 were indented with the dissector. Each disc was immersed in ammonium acetate buffer in a Sealed Container, and fluid from each Container was sampled at zero, one, three, six, 24, 48 and 72 hours and at one, and two weeks. The concentration of gentamicin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The fluid sampled at 72 hours from the indented discs containing 0.17 g gentamicin (0.88% w/w) contained a mean of 113 mcg/ml (90.12 to 143.5) compared with 44.5 mcg/ml (44.02 to 44.90) in the fluid sampled from the plain discs (p = 0.012). In discs containing 0.33 g gentamicin (1.75% w/w), the concentration eluted from the indented discs at 72 hours was a mean of 316 mcg/ml (223 to 421) compared with a mean of 118 mcg/ml (100 to 140) from the plain discs (p < 0.001). At two weeks, these significant differences persisted. At nine weeks the indented discs eluted a greater concentration for all gentamicin doses, but the difference was only significant for the discs containing 0.17 g (0.88% w/w, p = 0.006). However if the area under the curve is taken as a measure of the total antibiotic eluted, the indented discs eluted more gentamicin than the plain discs for the 0.17 g (0.88% w/w, p = 0.031), the 0.25 g (1.41% w/w, p < 0.001) and the 0.33 g (1.75% w/w, p < 0.001) discs. When preparing antibiotic spacers for use in staged revision arthroplasty surgery we recommend indenting the spacer with a MacDonald dissector to increase the elution of antibiotic.